This invention relates to novel 6,7-methylenedioxy-1-(2,2,2-trifluoroethyl)-4(1H)-quinolone-3-carboxylic acid esters and their use in the treatment of bacterial infections in warm-blooded animals. The novel free acid 6,7-methylenedioxy-1-(2,2,2-trifluoroethyl)-4(1H)-quinolone-3-carboxylic acid and its salts and alkyl esters of 1 to 3 carbon atoms are useful chemical intermediates.
U.S. Pat. No. 3,287,458 (to Kaminsky) discloses novel antibacterial 1,4-dihydro-1-lower alkyl-6,7-methylenedioxy-4-oxo-3-quinoline-carboxylic acids of the formula: ##STR1## wherein R is lower alkyl such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, or cycloalkyl such as cyclopropyl, cyclobutyl, cyclohexyl, or lower alkenyl such as allyl or vinyl and to the alkali metal salts thereof. R may also be a substituted lower alkyl such as hydroxy lower alkyl or carboxy lower alkyl or aralkyl, such as phenyl lower alkyl in which lower alkyl has the same meaning as defined.
The acid compound of the present invention differs structurally from that of U.S. Pat. No. 3,287,458 having an ethyl radical in the 1-position in that three fluorine atoms replace the hydrogen on the 2-carbon atom of the ethyl group. The 1-ethyl compound of U.S. Pat. No. 3,287,458 is known as oxolinic acid and will be referred to as such hereafter.
There is a need for new antibacterial agents as strains of bacteria can develop which are more resistant or immune to the antibacterial agents in use.